Derek was kindof right mate, drummings an individual thing, find out your own style and develop it. Sure he wasnt being specific with you but its because he simply worked on what was natural to him, you should do the same and then teach people about your technique :) I use the flat foot technique because I broke my left ankle playing sports once but i now use my ankle more to get up to speeds around 205-210bpm because its what feels natural to me. Just go with what your body is telling you to do when playing double bass and just go with the flow man lol